The present invention generally relates to a method of assembling a power transmission device and, more particularly, to a method of assembly using a conveyor defining a serpentine path.
Current methods of assembling relatively large power transmission devices typically involve using either synchronous or non-synchronous assembly lines. The assembly line is utilized to increase the rate of production per unit time by having a number of employees repeatedly perform specific tasks. Many of the assembly lines are constructed in either a straight or carousel-style arrangement.
Some assembly lines are configured such that operators have access to only one side of the line. Accordingly, the number of operations performed by a single operator may be limited because access to only one side of a workpiece is available. Furthermore, due to the relatively compact arrangement of most assembly lines, the operator will typically have limited flexibility to perform additional tasks at other workstations. Depending on the configuration of the line and the complexity of the tasks performed by an individual operator, some operators on the assembly line may experience significant down time while other operators are substantially continuously occupied by the tasks required at their station. Therefore, inefficiencies exist because each operator's time is not fully utilized. These inefficiencies correspond to reduced output from the assembly line.
Furthermore, if an operator is tasked with performing assembly operations at multiple stations, the operator is often required to walk relatively large distances either around or over a conveyor track. For a number of reasons, this is not deemed as an efficient use of the operator's time and energy.
A typical straight assembly line 10 is depicted in FIG. 1. As is shown, operators 12, 14 and 16 are positioned on a first side 18 of a conveyor track 20. An operator 22 is positioned on a second side 24 of conveyor track 20. A machine 26 is positioned between operators 14 and 16 to perform an automated process. It should be noted that operators 12 and 22 are positioned on opposite sides of conveyor track 20 in proximity to a workpiece 28 positioned at a first station 30. Because operations need to be performed on both sides of workpiece 28, two operators 12 and 22 are required to be positioned within close proximity of the workpiece while it is positioned at station 30. This is not necessarily an efficient use of manpower.
FIG. 2 depicts a typical carousel-style assembly line 40. In a carousel-style line, the workpiece travels on a conveyor system 42 defining a closed loop path. While the closed loop path of the carousel-type assembly line may more efficiently utilize floor space, similar deficiencies exist. For example, operators 44, 46, 48, 50 and 52 have access to only one side of the workpiece during the assembly process. Furthermore, due to the relatively spaced apart format of the straight assembly line 10 and the carousel line 40, multiple and possibly redundant tools are required to be mounted from bridge and rail type systems at multiple locations on the line.
Accordingly, it may be desirable to provide an assembly line having a conveyor system defining a serpentine path where an operator or assembler has access to a single workpiece at multiple positions along the conveyor system where the operator is required to move only very small distances.
It may also be desirable to allow a single operator access to both sides of the workpiece without requiring the operator to cross over the conveyor system or rotate the workpiece using a mechanical rotation device positioned along the conveyor system.